Keyboard mechanism for typographical machines



Nov. 9, 1943. s. w.- BEATTY 2,334,060

KEYBOARD MECHANISM FOR TYPOGRAPHICAL MACHINES Filed May 15, 1942 INVENTOR ccom BEATTY ATTORNEY Patented Nov. 9, 1943 KEYBOARD MECHANISM FOR TYPO- GRAPHICAL MACHINES George W. Beatty, East Stroudsburg, Pa., assignor to Intertype Corporation, Brooklyn, N. Y., a corporation of New York Application May 15, 1942, Serial No.--443,054

6 Claims.

This invention relates to improvements in certain elements of the keyboard mechanism as employed in commerical typographical machines of the general organization represented in U. S. Letters Patent No. 436,532, such machines being adapted for composing lines of character bearing matrices in response to manipulation of a keyboard and for subsequently casting type bearing slugs from such matrices. More particularly, it relates to an improved construction for that portion of the usual keyboard mechanismknown as the cam yoke guide plate which latter is provided with a series of vertically elongated slots through which the free ends of the usual pivoted cam yokes respectively project and are guided during their enforced pivotal movement upwardly under the influence of constantly rotating keyboard rollers on the cams carried by the yokes and during their vertical movement downwardly by gravity after completion of the aforesaid upstroke and when released in response to fingering of the keyboard.

As ordinarily constructed, the elongated slots in the aforesaid guide plate are parallel sided over their full extent in a vertical direction and only wide enough to avoid intimate contact therewith of the opposed vertical side facesof the free ends of the cam yokes as the latter swing up and down. A minimum of clearance is allowed because it is essential that twisting and side motion of the cam yokes be prevented so that their free ends will maintain full contact against and move in vertical alignment with the respective keyboard reeds disposed above them and which they operate during a portion of theirenforced upward stroke under the influence of the power driven keyboard rollers. It is well known, however, that unless scrupulously cared for at frequent intervals dirt and dust particles soon accumulate on the side walls of the guide slots and also on the surfaces of the free ends of the cam yokes with the result that the yokes bind-or become sluggish in action, especially in responding (dropping by gravity) when the yoke is released through operation of the so-called triggers actuated by the finger keys of the keyboard. Various arrangements have been proposed in an attempt to attain freer action of the cam yoke in its confining guide slot such as the insertion of a roller in the free end of the yoke and/or tapering of the sides of the latter in order to avoid excessive friction against the side walls of the slot. Such arrangements, however, have been found to be impractical for various reasons, the rollers for example acting only to accentuate the packing of dirt accumulations on t e sidewalls of the guide slots and thus objectionably reduce the effective width of the latter, and the necessarilysmall bearings of such rollers soon becoming-worn and clogged -with-dirt-so that the rollers jam. Tapering of the sides of theyoke end is objectionable because theresulting-smallside bearing surfaces rapidly wear and such reduced side bearing also permits the yoke to-twist which-is the very thing the guide-slotis intended to prevent.

The present invention aims to overcome the foregoing difiiculties by a simple and effective alteration in the formationor shape oithe slots in the cam yoke guide plate. Specifically, according to the invention, the side walls of the guide slots in which the free ends of the cam yokes operate are "formed-parallel-for closely confining the yokes-only over acritical portion of the vertical height of the slots, that is, onlyover their upperportion through whichtheyokes mustmove with littl .if anydeviationirom-a verticalpath whileoper-ating the keyboard reeds. .Below this critical portion the side walls of the slots are formed so as to diverge .ina downward direction to a point below the lowest level to which the free ends of the yokes are capable of descending when released, thu affording ample clearance around the ends ofthe .yokesfordropping freely by gravity in response to manipulation of .the keyboard. The arrangement'is such that when th cam yokes areidleorinnormal inactive position the opposed upper corners. of .their side faces aredisposed atabout'thelevel where the side walls of the slotbegin to diverge downwardly.

Th invention .will be clearly understood Iirom the followingdetailed description .of a. presently preferred embodiment thereof which is illustrated merelyby wayof example in the accompanying drawing in which:

Fig. 1 is a transverse verticalsection of a portion of the keyboardmechanism, showinga cam yoke and associated parts in normal or inactive position.

Fig. 1 is a fragmentary View of the camyoke guide plate shownin Fig. lbut'viewed from-the right in that-figura-the cam-yoke being shown in section where it passes through the guide slot of improved form according-to the invention.

Fig, 2is similar to Fig. lbut shows the cam yokeinthe down position to which it drops by gravity when released.

Fig. 2 is similar toFig. l but shows the cam yoke in section in released position in the improved form oi-guideslotin the guide plate.

Fig. 4 is a perspective view, partly in section; of a portion of the keyboard frame which sup ports the cam yokes and associated parts, the guide plate of improved form according to ,the invention being shown in place on the frame.

Fig. is a fragmentary view on an enlarged scale of a portion of the improved guide plate.

Referring to the drawing, and as customary for machines of the class referred to, the keyboard is provided with a series of cam yokes I- which are pivotally mounted on horizontal pins 2 fixed in supporting blocks 3 (desirably a separate block for each yoke in order to permit its independent removal) which are secured'to a rigid member 4 of the keyboardframe. Each cam yoke is formed with spaced side arms, Fig. 4, between which is mounted on a horizontal pin 5 the usual rotatable cam 6, the latter being disposed above and normally clear of the constantly rotating keyboard roller 1.

The numeral 8 designates one of the customary vertically reciprocable keyboard reeds, it being well known that there is provided a series of such reeds the lower end of each of which is disposed somewhat above and in vertical alignment with the free end 9 of its corresponding cam yoke. The reeds are usually formed from relatively thin strip metal so that their lower ends present only a narrow surface for engagement with the corresponding narrow top edges of the free ends 9 of the cam yokes. Thelreeds and yokes together constitute the means on machines of the class under'discussion for actuating the so-called. matrix escapements (not shown) for releasing the character bearing matrices from their storage magazine (not shown) in the process of composing lines of matrices.

For supporting the free ends of the cam yokes in normal orinactive position, as indicated in Fig. 1, there is provided theso-called triggers III which are pivotallymounted on a. common fulcrum rod 1 I, the latterbeing held in place as by passing through lugs arranged at suitable intervals along a rigid part of the keyboard frame, see Fig. 4. Beyond the spaced side arms of the cam :yoke the latter is formed with a solid portion which enables it to rest on the fiat top of the upwardly extending arm of its corresponding trigger, see Fig. 1, and the horizontal arm of each trigger is formed to engage and rock freely in a recess i2 near the upper end of a corresponding vertically disposed bar I3. The bars l3,one for each trigger, are supported for vertical reciprocating movement in a suitable fixed frame (not shownlfastened to a part of the keyboard frame proper (not shown) and are adapted to be moved upwardly a short distance in response to actuation manually of a corresponding finger operated character key (not shown) on the keyboard. The bars l3 are weighted so that they may drop by gravity the moment finger pressure on the character key is released. The manner of connection of the character keys to bars 13 and the specific construction and manner of operation of the keys and bars is of no direct concern to the present invention and is so well understood that illustration and description of the various details is deemed unnecessary for present purposes.

As usual, and as clearly shown in Fig. 4, the cams 6 are grooved around their periphery and provided part way around with teeth. Further, these cams are bored out as at M so as to be unbalanced or heavier at one side of their pivotal axis than at the other side. When the cam yokes i are in normal position where their free ends rest on the arms of their respective triggers ID, as indicated in Fig. 1, the periphery of the cams clears the rotating roller 1 and stop pin l5 which extend across the grooves in the periphery of each cam engage one side of prongs i6 formed on the so-called cam stop strip i1 suitably secured to a part of the keyboard frame. Pins l5 thus prevent the cams 6 from rotating in spite of their unbalanced condition until the yokes are released from their triggers whereupon disengagement of the pins from'the prongs I6 is effected. It will also be seen in.Fig. 1 thatthe free end 9 of the cam yoke I stands clear of the lower end of its corresponding keyboard reed 8 when the yoke is in the inactive position here indicated. As soon as a bar I3 is operated through striking its corresponding character key on the keyboard the trigger III which engages the operated bar is rocked counterclockwise to the position shown in Fig. 2 where it no longer supports its corresponding cam yoke. The yoke is, of course, immediately free to swing about its pivot 2 and drop by gravity to the position shown in Fig. 2 whereupon the periphery of the cam 6 is brought into contact with the roller 1 rotating in the direction indicated by the arrow, andsince dropping of the yoke has moved the pin l5 out of en agement with its stop prong I6 the cam is at once turned on its axis 5 by the roller 1, the rising contour of the cam then causing the yoke to swing upwardly about its pivot pin 2 to the position shown in Fig. 3. As the yoke risesthe top edge of its free end 9 encounters the lower end of the keyboard reed 8 at a point somewhat above the level at which-said top edge stand when the yoke is in normal or inactive position. The yoke then moves the reed upwardly far enough to actuate the matrix escapement which is aligned with the upper end of the reed, all in well known manner. When the cam 6 has been turned around far enough to bring the pin i5 therein into engagement withthe prong I6 the cam can rotate no further and its periphery is formed to recede or shorten radially just in advance of this point/S0 that upward urge on the yoke will of course cease. The yoke is then free to drop bi gravity back to the normal position shown in Fig. 1, it being recalledthat the weighted bar i3 drops by gravity immediately upon release of finger pressure on its corresponding key and thus rocks the trigger I'll to the position here shown where it is ready to receive and support the yoke the moment'the upward or operating stroke of the latter is completed.

During the up and down swinging of the cam yoke, and especially during its forced upswing due to rotation of its cam 6 by roller 1, it is essential that the free end 9 of the yoke be so guided as. to prevent it from twisting or artaking ofsuch side motion as might cause it to lose full contact against the lower end of the overlyingreed 8. For this purpose, and as already pointedout, the keyboard heretofore has been provided with a so-called cam yoke guide plate having a series of parallel sided vertical slots which afford such small clearance for the free ends of the yokes over their full range of swinging movement that dirt accumulations frequently cause the yokes to become sluggish in action or fail to operate. This faulty condition not only results in loss of production time but is often difiicult to avoid even in spite of reasonable care and inspection. Moreover, the operator of the machine may not even be aware of failure of a yoke to respond until the missing character in the line is discovered sometime later, thus necessitating resetting of the line to correct the error therein.

According to the present invention, the cam yoke guide plate 18 is provided with guide slots IQ of improved form, such slots having downwardly divergent side Walls 29 over the portion of their vertical height through which the free ends 9 of the cam yokes I project when in normal position as shown in Fig. 1, and also when in released position as shown in Fig. 2. In their upper portion the slots l9 are provided with parallel side walls 2i between which the free ends 9 of the yokes are confined against twisting and lateral movement during that portion of their upward swing in which they operate the overlying reeds 8, the side faces of the yokes being parallel (except for the slight hollowed-out central area as indicated) so as to provide a widened bearing against walls 2! and thus reduce wear and tendency-toward twisting. The side walls of slots 19 below the divergent walls 20 are also parallel and accommodate between them the lower arms of the triggers it with the necessary clearance for free rocking movement of the triggers by the bars l3.

It will be observed from Figs. 1 and 2 that the parallel walls 2| of the slot l9 intersect or merge with the divergent walls 20 at about the level of the top edge of the free end 9 of the cam yoke when the latter is in normal position so that in such position, Fig. 1 as well as in released position, Fig. 2 the side faces and top and bottom edges of the yoke stand entirely clear of these walls of the slot and afford ample clearance for a free gravity drop of the yoke from normal to released position in spite of dust or dirt particles which may lodge on the slot walls or on the sides and top of the yoke. Viewed in the reverse way, the walls 20 converge upwardly to a point of intersection with the parallel walls 2| located at about the level of the top edge of the yoke end when in normal position and somewhat below the level at which the yoke encounters the reed when moved upwardly by power. The converging and relatively loosely confining walls 25, therefore, serve to lead the free end of the yoke toward and into the space between the closely confining walls 2| as the yoke moves through the critical or reed operating portion of its upward stroke. From Fig. 3 it will be seen that the free end 9 of the yoke is guided for true vertical movement upwardly between the closely confining parallel upper walls 21 of the slot I9 and is thus kept vertically aligned for steady and full contact against the lower end of the reed 8 during the latter part or reed operating portion of the upward stroke of the yoke.

It may be pointed out that in Figs. 1 2 and 3 the width of slot [9, as represented, is somewhat exaggerated in order better to indicate the clearances that exist between the side walls of the slot and the sides of the free end of the cam yoke in all positions of the latter. As indicated above, the actual clearance between the parallel sides of the yoke and walls 2| during the reed operating stroke of the yoke is so slight as to closely confine the yoke for true vertical movement, any dirt accumulation on the proximate walls 2| being readily removed by the action thereagainst of the yoke itself while being forcibly swung upwardly, thus assuring a subsequent free downward swing of the yoke by gravity between these walls and back to normal position. It will be obvious, of course, that the actual form of the guide surfaces for the free end of the cam yoke may be varied, the invention contemplating in its broadest aspect the provision of any guide surfaces which provide a materially greater clearance for free movement of the cam yoke between normal and released positions than between normal and reed operating positions, and it being apparent that any surfaces which gradually converge upwardly either partially or wholly over the range of swinging movement of the cam yoke will serve the intended purpose.

Having thus described my invention, what I claim is:

1. Keyboard mechanism for a typographical machine comprising, in combination, a cam yoke supported at one end for pivotal movement in a vertical direction and having its free end provided with parallel vertical side faces, said yoke being adapted to swing by gravity from a normal position to a released position and to swing upwardly under the infiuence of power from said released position to a reed operating position above normal position, and a vertically disposed slot through which the free end of the cam yoke projects during such swinging movements, said slot having parallel side walls over the portion thereof through which the free end of the yoke projects while swinging between normal and reed operating positions and having downwardly divergent side walls over the portion thereof through which said yoke end projects while swinging between normal and released positions.

2. Keyboard mechanism for a typographical machine comprising, in combination, a cam yoke supported at one end for pivotal movement in a vertical direction and having its free end provided with parallel vertical side faces, said yoke being adapted to swing by gravity from a normal position to a released position and to swing upwardly under the influence of power from said released position to a reed operating position above normal position, and a vertically disposed slot through which the free end of the cam yoke projects during such swinging movements, said slot having parallel side walls spaced for closely confining the side faces of the free end of the yoke while swinging between normal and reed operating positions, and having downward extensions of said side walls spaced to afford a materially greater clearance between them and the corresponding side faces of the end of the yoke while swinging between normal and released positions 3. Keyboard mechanism for a typographical machine comprising, in combination, a cam yoke supported at one end for pivotal movement in a vertical direction and having its free end provided with parallel vertical side faces, said yoke being adapted to swing by gravity from a normal position to a released position and to swing upwardly under the influence of power from said released position to a reed "operating position above normal position, and a vertically disposed slot through which the free end of the cam yoke projects during such swinging movements, said slot having parallel side walls disposed opposite and in proximate relation to the side faces of the free end of the yoke over a limited portion of the slot through which said yoke end swings above normal position, and having divergent extensions of said side walls disposed opposite the side faces of the end of the yoke over the remaining portion of the slot through which the yoke end swings.

4. Keyboard mechanism for a typographical machine comprising, in combination, a cam yoke supported at one end for pivotal movement in a vertical direction and having its free end provided with parallel vertical side faces, said yoke being adapted to swing by gravity from a normal position to a released position and to swing upwardly under the influence of power from said released position to a reed operating position above normal position, and a vertically disposed slot through which the free end of the cam yoke projects during such swinging movements, said slot having an upper portion provided with parallel side walls spaced for closely confining the side faces of the free end of the yoke during the reed operating portion of its swinging movement, and having a lower portion provided with side walls which converge upwardly and intersect said parallel side walls at a point substantially at the a vertical direction from a normal position of rest downwardly by gravity to a released position and thence upwardly by power from the latter p0-,-

sition to a level above the normalposition, and guiding means for the free end of the yoke comprising surfaces so formed over at least a portion of their extent as gradually to converge in an upward direction toward the opposite sides of said free end of the yoke, whereby to increasingly restrict said yoke end against lateral movement while swinging upwardly by power. 7

6. Keyboard mechanism for a typographical machine comprising, in combination, a camyoke supported at one end for pivotal movement in a vertical direction from a normal position of rest downwardly by gravity to 9. released position and thence upwardly by power irom the latter position to a level above the normal position,

and guiding means for the free end of the yoke comprising opposed surfaces so disposed as to relatively loosely confine said yoke end against lateral movement while swinging between nor-- mal and released positions and surfaces so disposed as to closely confine the yoke end against lateral movement while swinging between normal and reed operating positions.

GEORGE W. BEA'I'I'Y., 

